Exam 2 Flashcards
(110 cards)
Where is insulin created?
beta cells of the islets of Langerhans in the pancreas
When is insulin released?
when levels of blood glucose rise
What are the 3 functions of insulin?
- stimulation of glycogen synthesis
- conversion of lipids into fats to be stored as adipose tissue
- synthesis of proteins from amino acids
What is the range of normal fasting blood glucose?
70 - 100 mg/dL
What is hypoglycemia?
- blood glucose < 70 mg/dL
- affects brain function
What is hyperglycemia?
blood glucose > 200 mg/dL
What is prediabetes?
- fasting blood glucose = 100 - 125 mg/dL
- impaired glucose tolerance (IGT)
What is the fasting blood glucose range for diabetes? What is the postprandial blood glucose for diabetes?
- fasting = 126+ mg/dL
- postprandial = 200+ mg/dL
What is postprandial blood glucose?
blood glucose after eating
What is an oral glucose tolerance test (OGTT)?
measurement of blood glucose after about 1 hour of ingestion of 75 g of glucose; usually done for pregnant women to test for gestational diabetes
What is A1c? How can A1c be used to determine diabetes?
– A1c = glycated hemoglobin
- diagnoses diabetes by assessing blood glucose levels over the past 3 months
- < 5.7% = normal
- 5.7 - 6.4% = pre-diabetes
- > 6.5% = diabetes
– when paired with a fasting blood glucose test on the same day, can determine diabetes diagnosis:
- if values for both are in diabetic range, confirmed DM diagnosis
What is DKA?
– diabetic ketoacidosis
- critical condition requiring immediate treatment
- develops in pts with no insulin reserves
- results in ketone production from the breakdown of fats for energy in the place of glucose
- results from hyperglycemia (lack of insulin) and ketosis
What are signs and symptoms of DKA?
- BG > 250 mg/dL
- pH < 7.3
- rapid onset
- low mortality rate
- occurs commonly in DM1 pts
How common is DKA in DM children?
1/3 of DM1 children first present with DKA
What is the pathology of DM1?
T-cells attack beta cells of the pancreas (autoimmune disorder)
What are the common symptoms of DM1?
- DKA – usually presenting sign
- polyuria
- polydipsia
- polyphagia
What is hyperosmolar-hyperglycemic syndrome (HHS)?
– caused by hyperglycemia (lack of insulin) and dehydration
- hyperglycemia
- lack of insulin
- gluconeogenesis in response to lack of insulin
- glycogenolysis in response to lack of insulin
- hyperosmolarity
- osmotic diuresis from high blood glucose
- polyuria
How quickly does HHS develop when compared with DKA?
HHS develops over days to weeks; DKA develops within hours
What are the symptoms of HHS?
- weakness
- poor tissue turgor
- tachycardia
- rapid, thready pulse
- confusion
- polyuria
- polydipsia
- coma – 25% of pts present with this
- gradual onset
- BG > 600 mg/dL
- pH > 7.3
- high mortality rate
- occurs rarely in DM2 pts
What are some causes of HHS?
- infection (pneumonia, sepsis)
- noncompliance with DM medication
- substance abuse
- coexisiting diseases
Who typically gets HHS?
DM2 pts
What are some treatments of HHS?
- FIE
- fluids
- insulin
- if insulin is replaced before fluids, ECF water will move into ICF
- will worsen hypotension and could lead to shock
- electrolyte replacement
What is the Somogyi effect?
– morning hyperglycemia due to:
- excessive insulin therapy or insulin peak during sleep causing hypoglycemia
- compensatory mechanisms raise blood glucose by morning (rebound hyperglycemia)
- epinephrine, norepinephrine, cortisol, glucagon, etc. increase blood glucose levels
– it is essentially hyperglycemia in response to hypoglycemia
– occurs more commonly in DM1 pts
What should DM pts do to prevent the Somogyi effect?
- adjust insulin amounts as needed
- decrease dose
- take earlier
- take snack with evening dose
- avoid eating carbohydrates at night